Cutout



Aug.y 4, 1942.y A A RAMSEY 2,291,646

f :UToUT Filed July s, 1934 4 sheets-sheet 1 A. RAMSEY Aug. 4, 1942..

CUTOUT Filed July 9v, 1934 4 sheets-sheet 2 I Aug. 4, 1942.

CUTOUT Filed July 9, 1934 A. RAMSEY 4 Sheets-Sheet 3 Aug. 4, 1942. j A. RAMSI-:Y 2,291,646

CUTOUT Filed July 9. 1954 4 Sheets-Sheet 4 Patented Aug. 4, i1942 OFFICE Allan Ramsey, Evanston, El., assignor to Schweitzer & Conrad, lne., Chicago, Ill., a corporation of Delaware Application July Si, i934, Serial No. 734,262

(El. Zilli-iid) 73 Claims.

My invention relates to cutouts for electrical circuits.

More particularly, my :invention relates to an improved cutout for the primary circuits of an electrical distribution system. Primary circuits usually extend from electrical substations, or transformer stations on a high potential line, out over the immediate vicinity, and supply current to the service transformers forl light and power distribution. Such circuits commonly carry potentials in the neighborhood of 7,500 volts, the voltage being sometimes less than this and sometimes slightly higher.

It is common practice to install primary cutouts in the primary leads of the distribution transformer. The function of the cutout is automatically to disconnect from and isolate from the feeder circuit a transformer which breaks down or is otherwise either partially or completely short-circuited. By thus isolating a defective transformer or a defective section of the ruse adapted forconnecting the terminals within the housing when the cover is closed.

While the particular device which I shall de scribe hereinafter in connection `with the drawings is a cutout of the type referred to'in the preceding paragraph, it is to he understood that the invention is not limited in all respects to cut- Aout devices of this type, but may he employed in similar or equivalent devices as suitable or desired.

` @ne of the objects of my invention is to provide improved means for producing a positive arcing gap and for extending the same when the iuse melts. This positive formation and extension of the gap upon melting of the fuse is of great virtue. With the'presentinvention the action is not dependent upon the amount of current melt ingV the fuse, as in ordinary expulsion fuses which depend on gas pressure generated by the arcing to extend and quench the arc, and positive and dependable operation, during either light overload of heavy short circuit, is assured.

Another object is to provide means for locking the fuse, or other'device, to at least one of the contacts and/or the cover for the housing, closed position, and improved means lor releasing this locking means upon an interruption in current flow, or when the fuse melts.

Another object is to provide means which will serve the dual purpose of producing a positive gap and extending the same when the fuse melts, and which means will also serve to release the means for locking the fuse, or other device, to at least one of the contacts and/or the cover in closed position.

Another and more specific object is to provide leverage means for normally holding the gap producing and extending and/or lock releasing means against operation, and which will produce and extend the gap rapidly upon melting of the fuse, positively to open the circuit and stop the now of current before too much heat is developed. I

Another object is to provide for normally re-v chorage for anchoring the fuse link in restraining relation, and more particularly to the leverage means for normally holding Vthe device against operation and for extending the gap rapidly when the fuse melts.

Another object is to provide a combination hinge and drop-out-stop and recoil stop, prefern ably remote from the charged terminal, although it may he adjacent or a part of the terminal, within the broader aspects of this feature of the invention. This combination hinge and dropout and recoil stop prevents the rcover and fuse from dropping out, and takes the recoil action.

Another object is to provide an improved contact and locking clip, an improved tube terminal arrangement with contact and locking means for engagement with the contact and locking means of the clip, and an improved contact spring arrangement for pressing the clip into iirm engagement with the cooperating means on the terminal.

Another object is to provide an improved lower contact assembly having an improved arrangement or the contact ngers for yieldingly engaging the terminal which cooperates therewith, and an improved contact spring arrangement for pressing the contact lingers into rm contacting engagement with the cooperating terminal.

The fuse link assembly which employ is preieraloly of the type described and claimed in my Patent No. 2,091,453, `with means attached to the terminal to which the closely surrounding inner sleeve oi the fuse link is secured for anchoring or holding this terminal electrically to the upper terminal ofl the outer sleeve.

En the illustrated embodiment of the invention, the outer fuse sleeve or tube;y is secured to the cover for the housing and is, in turn, carried for movement slidably by a hinge member hinged to the housing. The upper end of the fuse has contact and locking means for engagement with the contact and locking clips in the housing when the cover is closed, and a compression spring is and permit the fuse and cover to drop, by gravity, to open position when the fuse blows. The fusible link is anchored at its upper end to the upper fuse terminal and extends downwardly through the tube and from the lower open end thereof for anchorage to a lever which is adapted to restrain the spring in compression by cooperating with one of thefuse brackets through a relatively short lever arm and anchorage to the fuse link through a relatively long lever arm. This gives the fuse link mechanical advantage over the spring and at'the same time, upon blowing of the fuse, the lever operates to extend the gap rapidly, or with great speed.

Further features and advantages, and a concrete understanding of the present invention, will be more apparent from the following detailed description taken in connection with the accompanying drawings, in which:

Figure 1 is a view illustrating my improved form of cutout mounted upon a cross-arm, with the cutout in side elevation and the cover thereof in closed position, the open position being shown by broken lines;

Figure 2 is a top plan view of the same;

Figure 3 is a front elevational view of the cutout with the cover removed;

Figure 4 is a vertical longitudinal section forwardly arched portion II is integral with the back wall 8, and at its opposite ends with the side walls 1, 1, and acts as a spacer to reenforce the side walls 1. 1 against convergence, particularly in ring.

Extending inwardly into the arched portion Il from the back of the housing is a pocket I2 in which a mounting tongue I2 is secured by means of cement or a suitable alloy I8'. 'Ihe inner surface of the pocket I2 is preferably grooved, as shown in Figure 5, to bond the cement or alloy securely in place. The tongue I8 is attached, for example, to the cross-arm I4 of a transformer pole or other support by a bracket I5. This bracket I5 comprises four bracket parts I5, I1. i8 and I9, and is similar to the bracket described and claimed in my Patent No. 2,108,348. The bracket part I8 ts upon the top of the crossarm I4 and has one end turned down along one side' of the cross-arm. The part I9 nts against the opposite side of the cross-arm and has its lower portion oiiset or turned in beneath the bottom of the cross-arm. These parts I8 and I9 have outwardly directed flanges 28 at their opposite ends. The part I8, which is of L-shaped form,

. is fitted against the bottom of the cross-arm with through the housing and cover of the cutout, A

' contact parts and cover in elevation and the cover in open position;

Figure 6 is a longitudinal section through the fuse device, showing the same in position on the cover;

Figure '1 is a fragmentary detail section taken on the line 1-1 of Figure 6;

Figure 8 is a perspective view of the upper contact block, clip and spring assembly;

Figure 9 is a perspective view of the lower contact block, clip and spring assembly; and

Figure 10 is a perspective view of one of the hinge members.

The embodiment of the invention illustrated in the drawings comprises a housing 5 which is adapted to be exposed to the weather, and houses the main contact terminals.

The housing 5 comprises a unitary body consisting of a back wall 5 from which extends forwardly an integral rim forming substantiallyparallel side walls1, 'I and atop wall 8, leaving the front open at 9 and the bottom open at I0. The back wall 5 has an arched portion II extending forwardly toward the open front and transversely between the side walls 1, 1 approximately midway of the height of the housing 5. The back wall 5, forwardly extending rim and arched portion I I are preferably formed as a unitary piece of dense wet processporcelain or other suitable insulation, and the entire housing is preferably finished with a chocolate glaze inside and outside. The

its flange 28 in spaced relation to the flange on the adjacent end of the part I9 and its free end extending out from the oppomte side of the crossarm, and the part I1 is applied with its base against the side of the cross-ann between the flange 28 on the part I8 and the extending end of the clamp part I8, and with one of its 25 in spaced relation to the flange 25 on the adjacent end of the clamp part I8 and its other flange 28 adjacent the extending end of the part I8. The tongue I8 is swlveled between the extending end of the clamp part I8 and the ange on the adjacent end of the clamp part I1 upon a carriage bolt 2| which maybe loosened to permit the cutout to be adjusted or swung to any angular position about the axis of the bolt 2| and tightened to clamp the cutout rmly in the position in whichit is arranged. Carriage bolts 22 pass through the other pairs of spaced flanges 28 for gripping the bracket iirmly in place about the cross-arm Il.

The upper contact disposed within the housing 8 comprises a contact block 25 and a pair oi' contact clips 25. The block 25'is preferably conc structed of cast hard bronze. or other suitable conducting material. This block 25 is provided integrally along the top witha thickened lug having a transverse opening 21 for receiving, from either side, the bared end of one line wire 28, and a pair of screws 29 are provided for binding the inserted end of the line wire 28 in place. Openings are formed in the side walls 1. one adjacent each side oi' the contact block 25 to permit leading the conductor 28 into the housing 5 from either side. The inner ends of these openings are preferabLv inclined upwardly for the purpose of preventing moisture from entering the housing through these openings. The base of the block 25 has a pair of laterally spaced integral studs 32 which `may be uted or formed irregular within .their length. and are secured by cement or alloy at 33 in laterally spaced recesses 34 in the back wall 8. The inner surface of the back wall 5, upon which the base of the block 25 seats, may be finished as shown in Figure 4, and iillets of cement or alloy may be provided at 85.

The clips 25 are preferably constructed of phosphor bronze or other material of good conductivity. Each clip 26 is of generally L-shaped form with its short up-turned base end secured by a screw 36 to the contact block 25. The clips 26 are'spaced apart transversely of the housing 5, as shown in Figure 3, to receive between them the upper end of the fuse, and the outer end of each clip 26 terminates in a V-shaped contacting and locking end` 38. L-shaped contact springs d have their up-turned base ends secured with the clips 26 to the contact block 25 by the screws 36. These springs 40 are formed of strips of suitable spring stock, and their longer outstanding arms bear downwardly on the respective clips 26 to force, when the cover 44 is in closed position, the contacting and locking ends 38 of the clips 26 into rm contacting and locking engagement with contact and locking studs 42 extending laterally in opposite directions from the upper iuse tube bracket 43.

The lower contact means comprises a contact block 46, contact clip 41 and contact spring 48. The block 46, which is preferably constructed of cast hard bronze or other suitable conducting material, is mounted upon the back wall 6 below the arched portion Il by means of a pair ot integral laterally spaced studs 49 which may be' luted or formed irregular within their length andare secured by cement or alloy at in recesses 5I in the back wall 6. The inner side of lopening 53 for receiving from either side the bared end of the other line wire 28, and the opposite sides of the top of the block are thickened to receive screws 54 provided for binding the inserted end of the line wire 28 in place.

The clip 4l, which is preferably formed of a strip of phosphor bronze or other suitable conducting material, has a nat end secured to the forwardly and downwardly directed inclined surface on the block 46 intermediate its opposite sides by means of a pair of screws 56. At the upper end of its ilat lower portion, the clip (El is rounded around the correspondingly rounded surface of the block 46 intermediate its opposite sides, and the free upper end of the clip is of generally inverted lJ-shaped or goose-neck form. `lhe free end of the goose-neck contact part of the clip is slotted at 56 to form spring contact ingers 59 for relatively great resiliency of contact with the hinge sleeve member t@ which constitutes the lower terminal of the fuse. The contact spring 48 is formed of a strip of suitable spring stock and has its nat lower end secured with the lower end of the clip lill to the block d6 by the screws 56. The upper portion of this spring it is of generally goose-neck form corresponding with the iorm of the upper end of the clip ill, and is nested within the upper end oi the clip @l with its substantially flat free end bearing against the free ends of the contact ripm gers 5d to force these fingers outwardly into firm contacting engagement with the terminal' forming hinge sleeve till when the cover il@ is closed. The upper portion oi the block dit is slotted intermediate its opposite sides to receive the adjacent portions of the clip Gil and spring dit, and the side walls 5, 'i of the housing have openings 625 adjacent the opposite sides of the block d@ for leading the lower line wire 28 into the opening 53 in the block d@ from either side. The inner ends of the openings t2 are preferably inclined upwardly for the purpose of preventing moisture from entering the housing through these openings.

Secured in transversely aligned positions to the inner surfaces of the side walls 1, adjacent their lower ends and beneath the lower contact block 46, are a pair of hinge members 65 These hinge members 65 are preferably constructed of cast hard bronze or other suitable material, and each member has a pair of studs 66 integral with the member and extending from its base. These studs 66, which may be uted or otherwise formed irregular within their length, are secured by cement or alloy at 6l in recesses 68 in the side walls l', l'. The lower ends of the side walls Tl, l are thickened outwardly to accommodate adequately the recesses 68, and the back wall 6 may be thickened to accommodate adequately the recesses 34 and 5l.

Referring now to the detailed construction of the cover and fuse assembly, the cover 44, which is preferably formed of brown Bakelite or other suitable insulating material, loosely fits, when in closed position, within the front opening d of the housing 5. The upper end of the cover has a pair of outwardly extending and laterally spaced manipulating eyes or rings lli, one adjacent each of the opposite sides 'of the cover, to receive the end of a hook stick itl' (Fig. l), for manipulating the cover to open or closed position with the hook stick. A third manipulating eye or ring li.' disposed laterally along the top of the cover and extending outwardly between the upper end of the eyes lt, is also adapted to receive the end of the hook stick for ,manipulating the cover in removing the same from and inserting it into hinged engagement with the hinge member 65. The eye-carrying upper portion of the cover is thickened at l2, and the thinner lower portion of the cover may be provided with strengthening ribs iii.

'lihe tube @il and the attached cover M are hinged at the lower end by means or the hinge sleeve member titi. This member constitutes the lower fuse terminal and is preferably constructed of cast hard bronze or other suitable material. it comprises a sleeve portion td, bored at 'i5 and counterbored at it to form, at its upper end, an internal shoulder liti. Integral with the opposite sides or" the sleeve portion 'ill and disposed in diametrically opposite positions are a pair of arms d@ which entend downwardly below the sleeve portion lid, The lower ends of these arms (lll are dared to widened form, and the widened lower end oi each has a pair of integral hinge studs projecting outwardly therefrom. The two studs ci each pair are disposed obliquely .with respect to each other and are adapted to 82 to prevent the cover and fuse from dropping out of place when in the open position of the 4cover as shown in Figure 5. The lower wall Sii',

which cioses the lower end of the lower and outwardly disposed groove S3, is turned up and hooked in at its outer end at 36 to Vtake the recoil oi the tube upon blowing of the fuse and to hold the cover and ruse from dropping out, parlm ticularly when the cover is in closed position,

as shown in Figure 4. The upper side of the upper groove I3 is bordered by an integral wall or flange l1, the lower end of which extends in at Il and closes the lower end f the upper groove Il. Walls Il and 81 also serve to guide the hinge pins 82 into place in hlngedly attaching the fuse tube and cover to the housing. l

The rear walls l1 of the hinge members 6I have a further and important function. As the cover and tube are raised from open position, as shown in Figure 5, the wah l1 of each hinge member, by engagement with the upper pin 82, forces the lower pin l! outwardly under the inwardly hooked upper end of the recoil and dropout stop It which, thereupon, by its hooked engagement with the lower pins 82, prevents lifting the cover out of the hinge in the closing and opening movements. This hooked engagement also prevents lifting the cover out of the hinge when the cover is closed. The cover may be lifted out of the hinge only in substantially full open position f the cover, As the cover reaches full open positionthe lower pins 82 move inwardly to position, clear of the inwardly hooked ends oi' the stops 8l, and in this position the contour of the wall Il permits the lower pin 82 to be lifted to clear the upper pin 82 of the stop 8S, whereupon the cover is lifted out of the hinge.

The fuse which I employ in my improved cutout comprises an insulating outer sleeve or tube Il, preferably formed of linen Bake1ite" tubing ll, rolled on a fiber liner 92. The lower end of the sleeve 90 is reduced at 93, and this reduced end l! passes slidably through the sleeve portion 1I of the hinge sleeve 60 and is threaded at its lower end at il into the internally threaded sleeve or ferrule part of the lower fuse sleeve or tube bracket 98. y

The bracket I6 is preferably formed of cast hard bronze or other suitable material, and has integral mounting portions 91 secured firmly to the inner surface of the cover u by screws 98. These mounting portions $1 are spaced transversely to form an opening 99 through which a pair of arms I NI, integral with the front of the sleeve part 'I4 and depending downwardly therefrom, and a contact lever I l2, are adapted to operate.

A spring wire compression spring I, coiled about the reduced lower end of the fuse tube ll and having its upper portion disposed within the counterbore 1B, reacts between the ferrule or sleeve part of the lower tube bracket Il, secured to the cover M and to the slidable fuse tube Il, and the shoulder 18 at the upper end of the hinge sleeve Il, and tends normally to move the fuse tube and cover downwardly with respect to the hinge sleeve Il. This downward movement is limited by engagement of the upper end of the hinge sleeve Il with the shoulder Ill formed in the tube 0l by the reduced lower portion thereof. The -shoulder Ill may be omitted and the tube formed of reduced diameter throughout its llength. However, by pulling the fuse sleeve 9| from the hinge sleeve Il to the position shown in Figure 4, the spring I is put into compression and the contact or locking pins 42 are separated from the hinge pins l2 to such an extent that when the hinge pins 82 are engaged in the grooves Il in the hinge members 8l, and the cover swung to closed position. the contact and locking pins 42 will snap inyfbehind the eontact and locking ends Il of the upper contact clips 26 to lock the cover closed and the clips 2i in firm contacting engagement with the pins 75 42 of the upper terminal forming tube bracket I3. The spring I is normally restrained in compression by the fuselink Ill.

The fuse link, designated in its entirety at I", is identical with the fuse link described and claimed in my Patent No. 2,144,707, with the button Ils, of suitable conducting material and flanged radially, threaded upon the upper end of the upper fuse terminal III. By removing the button Ill, the threaded upper end of the terminal I Il is adapted for threaded engagement with ,the lower cable terminal and spring fastener shown in my Patent No. 2,144,707. The terminal I'Il is formed of copper or other suitable or preferred material.

The lower fuse terminal Il! is formed of simllar material, and this terminal and the terminal lil are connected by a strain wire or tensile element I Il arranged to bear the mechanical strain. The upper end of the wire IH is inserted in a socket or opening in the lower end of the terminal IIII and is secured rigidly in place as by punching at IIl the stock of the terminal Ill into firm binding engagement with the wire, or by flattening the socket rmly upon the wire. The lower end of the wire Ill is inserted in a socket or opening in the terminal Il! and is secured rigidly in place as by punching at I'IO the stock of this terminal into ilrm binding engagement with the wire, or, as before, by flattening the socket upon the wire.

The fuse wire III is preferably of silver, and the strain wire is preferably of nickel chromium wire. The upper end of the fuse wire Ill is inserted in an opening in the terminal III and is secured firmly in place therein as by punching the adjacent side of the terminal into firm engagement therewith or flattening the same thereon. The lower end of the wire IIS is inserted in an opening in the terminal H2, and may be secured firmly In place therein as by punching the adjacent sides of the terminal II2 into firm Aengagement therewith. or flattening the same thereon. Intermediate its ends, the fuse wire lli is coiled about the strain wire I Il.

It has been found that silver, as used in devices of this sort, has unusual characteristics. First, there is not an appreciable absorption of oxygen until temperatures close to the melting point are reached, and this oxygen is released again upon a slight drop in temperature. Even if there is some oxidation, the oxide has conducting properties similar to those of silver. Also, it has been found that under certain circumstances silver will form undesirable compounds with other elements. on blowing. In some of the experiments and tests made on fuses under various conditions, the blowing oi' the fuse appeared to be more violent than the power current would seem to account for.

By a combination of the silver fusible element with the outer insulating sleeve and the inner insulating sleeve closely surrounding the inner fuse terminals and closed by and attached to the upper fuse terminal, the silver fusible lelement is excluded from too free access to atmosphere and, by the close surrounding of the lower fuse terminal by this inner sleeve. and with the movement of this lower terminal within the sleeve. this exclusion is maintained upon blowing of. the fuse. 'I'he lower fuse terminal is movable within the inner sleeve for elongation of the arc within this sleeve. and is movable from the inner sleeve to release the pressure and permit an outward flow of gases from the inner sleeve.

suitable material.

accinge ance strain wire H4 lboth are completely en; closed and shielded from atmosphere, gases and moisture, by the inner tube |20 formed of liber or other insulating material. The upper end o the tube |20 closely surrounds the upper fuse terminal H beneath the integral flange lli thereon, and is shrunk or crimped at it?? into the annular groove U23 to close the upper end of the tube |20 against access of atmosphere to the silver fusible element and to secure the tube |20 to' the upper fuse terminal lill. The lower end of the tube |20 passes freely over and closely surrounds the lower fuse terminal M2. The bore of the sleeve it@ along the terminal lli? is of substantially the size of the stress sustaining and fusible link surrounding portion or said bore and substantially closed by the terminal M2, yet 'unrestricted when the terminal lill moves from the sleeve' |2il. The tube or sleeve it@ oi- 'iers no impairment to free separation or' the terminals il@ and E52 upon blowing of the fuse, yet, at the same time, it is rigid throughout its length and by its engagement at the upper end with the terminal H0, and its cooperation with the terminal M2 holds the terminals il@ and l l2 rigidly against relative lateral movement such als otherwise might result in movement, or even crimping or twisting, of the fuse wire i i@ and/or strain wire lill.

For the purpose of holding the fuse set with the spring lut in compression and the tube Si@ and cover dll extended upwardly from the hinge sleeve 'irl as shown in Figure Al, the lower end of the terminal lili! is provided with an extension |25 formed of stranded conducting cable or other Several strands of copper cable, preferably tinned, or depth cable, are employed in the illustrated embodiment, although this may, of course, vary widely. The upper end of this vcable is inserted in a socket ldd on the lower end of the terminal i l2, and this socket is ilattened into ilrm engagement with the cable to secure the same therein. Within its length, the stranded cable |25 may be provided with a conical bushing |28 securely anchored in position upon the cable as by attening theupper end of 'the bushing into rm engagement with the cable at |29. The purpose oi this bushing is for holding the fuse set where the fuse link is employed in the plug and socket type of cutout described and claimed in my copending application above identilied.

The upper fuse tube bracket 43 Iis preferably formed of cast hard bronze or other suitable material. Its sleeve portion |06 is internally threaded at |30` for threaded engagement with the upper end of the tube 90, and it has an integral mounting bracket |32, the laterally extending base flanges of which are secured by screws |33 tothe inner side of the cover 44. The bracket |06 also has an upwardly extending tubular portion coaxial with the sleeve portion threaded upon the tube 90, and this upwardly extending portion is externally threaded at |35 to receive a contact cap U36 formed of cast hard bronze or other suitable material. The button |109 abuts the upper end of this tubular portion and anchors the upper end of the fuse link thereon, and the under side of the top wall of the cap |130 is recessed centrally at |139 to assure clearance of the threaded upper end of theterminal i l0 should this terminal project slightly from the top of the button Mit.

The extension or stranded cable |25 constitutes a tail extension which, when the spring lilitl is in compression with the fuse tube and cover extended, extends down below the lower end of the fuse tube or casing so that it may be gripped conveniently for restraining the spring and holding the tube 90 and cover di in extended position.

For the purpose oi anchoring the fusible element and ccnnnecting the same electrically at its lower end to the terminal forming hinge sleeve til, the contact lever H92, preferably formed or cast hard bronze or other suitable material, is pivoted at M3 between the lower ends of the arms Mill.. This lever has an l.shaped slot Mld, one leg o which opens from one side or the lever, and positioned in the other leg of the slot is an eccentric clamp or segment Bilt pivoted at lill to the lever |02. The arcuate surface of the eccentric clamp or segment llt is knurled at [Idil and the opposed side of the L-shaped slot ldd is also preferably knurled for firm gripping engagement with. the cable |125.

With the parte in the positions shown in Figure 6, the tube @il is drawn from the hinge sleeve t@ to the extended position shown in Figure fl, whereupon the eccentric clamp |00 is swung into position so that the cable i255 may be insemed into t e slot M5 into position beneath the clamp MG. The clamp it is then swung .about its pivot illl to bring its eccentric portion toward the underlying part of the lever M32, and its lrnurled edge into firm wedging and biting engagement with the cable i125.

in anchormg the cable to the lever M32, this lever is swung into position underlying the sleeve part ci' the tube bracket il@ and cooperates with thetube bracket Qt throughga relatively short radius at i5@ to hold the iuse set. rlhe anchorage of the ruse link to the lever |102 is through a relativelylong radius atiiil, and the fuse is thereby given e, mechanical advantage over the spring lull. At the same time, when the fuse blows and the lever M32 is freed, the downward movement o the tube and cover acting on the lever illu through the relatively short radius and the lever being connected to the fuse link through the relatively long radius, a compound leverage is produced which forms and extends the arcing gall@ rapidly Upon blowing of the fuse, the restraining action of the fuse link is released and the spring ,lull moves the fuse tube 90, cover M and contact and locking pins l2 downwardly, thereby shortening the distance between the hinge pins 82 and the contact and locking pins` 42 and releasing the pins ill from their contacting and locking engagement with the contact and locking clips 26. The cover lll is oH-center with respect to the hinge mounting of the member '14, so that,

when the pins 42 are released from the latch 38, the fuseand cover drop by gravity to the open position shown in Figure 5. 'I'he opening movement is limited by engagement of the inwardly and upwardly disposed pins 82 with the stop I5 on the hinge members 65.

To reset the fuse after blowing, the cover and blown fuse are removed from the housing and a new fuse applied. The fuse and cover are moved upwardly to extended position with respect to the hinge bracket and the tail extension is anchored between the knurled surfaces as previously described. The hinge pins I2 are then inserted into -the grooves in the hinge members in the housing and the cover may then be swung to closed position, snapping the pins 42 into locking engagement and firm contact with the clips 2i. A circuit is thus established from the upper clips 26 through the pins 42 and upper tube bracket I3, upper fuse terminal I Ill, strain wire and fuse link assembly III and IIB, lower fuse terminal H2, stranded conductor i25, lever and latch |02, |46, and lower hinge sleeve or hinge bracket 60 to the lower contact clip 41.

The fuse clears minor, or low current faults, as positively as it clears more severe faults, as during short circuit or heavy overload. Its operation does not require explosive action, but in all cases the instantaneous freeing of thespring I establishes a definite and sumcient gap, regardless of the amount of fault current. At the same time, short circuit and heavy overload faults are cleared without attendant danger that excessive pressure may cause destruction of the equipment. Heavy pressures occur within a small cylinder or chamber which is a part of the fuse link, and the tube proper is freely vented. lPreheating or corrosion does not deteriorate and result in causeless" operation of the fuse element,

because this element is made of metal which has proved to be vastly superior from the standpoint of its resistance to corrosion and its ability to 1 operate at a higher percentage of its melting point without deterioration. It is not necessary to replace unblown fuse links after an over-current has blown other fuses in the same circuit, and a permanent and exceptional accuracy of fuse ratings is obtained. The time delay characterlstic and short arcing time make the fuse exceptionally suitable for selective operation.

`In the illustrated embodiment of the invention, the spring I and lever means Il! work in the same direction to produce a positive gap and to elongate rapidly the gap, but it is to be understood that the spring and lever means may work in opposite directions within the scope of the present invention.

It is to be understood further that. instead of anchoring the fuse link to the lever |02 by means of the eccentric clamp |46, the link may be anl chored by means of a screw, or in any other suitable or preferred manner.

While I have shown and described my invention with reference to the particular details of construction of one embodiment, it is to be understood that the invention may appear in diiferent forms and with numerous modifications and variations such as will suggest themselves to one skilled in the art, and it is to be further understood that I consider all such modifications and variations to be includedv within the scope of my invention.

'.l. Ina fuse, an insulating outer sleeve having spaced terminals, a fuse link connected between said terminals and disposed within said sleeve.

and means for producing a positive gap and for extending the gap when the fuse blows, said means comprising lever means and a coaxial coiled spring embracing the outside of the sleeve and reacting against the lever.

2. In a fuse, an outer fuse tube having spaced terminals, there being relative movement between said tube and one of said terminals, a fuse link in the tube, and means for translating the relative movement between said tube and terminal to produce a positive gap and extend said gap when the fuse link blows said means comprising a lever pivoted to the relatively movable terminal. said link being attached to the lever.

3. In combination, a sleeve member constituting a terminal, a fuse tube slidable in said sleeve member, a second terminal for said fuse tube, a bracket for said tube, aY compression spring coiled about said tube and reacting between the sleeve member and said bracket to move the tube with respect to said sleeve member, a lever pivoted to said sleeve member, and a fuse link held in electrical connection with said second terminal and adapted to be anchored to said lever for electrlcal connection with the sleeve member and to restrain said spring.

4. In combination, a fuse link, a pivoted lever, a self energizing clamp pivoted to said lever and having a knurled surface for wedging the link into engagement with the lever to anchor the link to the lever and spring means for placing the link under tension to facilitate parting of the link and for energizing the clamp.

5. In combination, a fuse link, a pivoted lever having a knurled surface, a self energizing clamp pivoted to said lever and'having a knurled surface for wedging the link into engagement with the knurled surface of the lever to anchor the link to the lever and spring 'means for placing the link under tension to facilitate parting of the link and to energize the clamp.

6. In combination, a fuse link, a pivoted lever of said slot opening from one side of the lever to receive said link, cam means in the other leg of said slot for engaging the link to anchor the same to the lever'and spring means for placing the link under tension to facilitate parting of the link and to energize the clamp.

7. In combination, a pair of contacts, a fuse for connecting said contacts, said fuse comprising a fuse tube having spaced terminals and being movable relative to one of them, means for locking the fuse to at least one of said contacts, and means for moving the fuse tube longitudinally relative to said one of said fuse terminals to release said'locking means.

8. In combination, a pair of contacts, a fuse for connecting said contacts, said -fuse comprislng a fuse tube having spaced ferrules providing terminals, said tube being movable relative to one of said ferrules, means for locking the fuse to at least one of said contacts, and means for releasing said locking means by relative movement between the fuse tube and said one of the ferrules of said tube.

9. In combination, a hinge member, a bracket member, a fuse having a tube slidable in said hinge member and secured to said bracket member, and means for producing relative movement between the hinge member and the bracket member to forma positive gap and extend said gap when the fuse blows.

10. In oolnbination, a housing, a cover for said prising a fuse tube open at one end and having anemie spaced terminals, locking means for the cover, and means for -moving the fuse tube longitudinally to release said locking means.`

11. In combination, a housing, a cover for said housing, a fuse on said cover, said fuse compris ing a slidably mounted fuse tube having spaced fuse tube terminals adapted to be interconnected by a fuse link within said fuse tube, locking means for said fuse tube, and spring means for producing relative movement between said fuse tube and one of said fuse tube terminals to release said locking means upon parting of said fuse link. v

12. In combination, a housing, a hinge member hinged to said housing, a cover for said housing, a pair of tube brackets on said cover, and a -fuse tube carried by said brackets and slidably movable in said hinge member.

13. In combination, a housing, a hinge member hinged to said housing, a cover for said housing, a pair of tube brackets on said cover, a fuse tube carried by said brackets and sllidably movable in said hinge memben'and a compression spring coiled about the tube and reacting between the hinge member and one of said tube brackets.

14. In combination, a housing, a hinge member hinged to said housing, a cover ior said housing, a pair of tube brackets on said cover, one oi said brackets forming a terminal for a fuse tube, a fuse tube carried by said brackets and slidably movable in said hinge member, a compression spring coiled about the tube and reacting between the hinge member and one or said tube brackets, said hinge member constituting a second terminal for said tube, and a fuse iink connected between the terminal forming bracket and the hinge member and adapted to be anchored to restrain said spring.

15. In combination, a housing, a hi Iige member hinged to said housing, a cover for said housing, a pair of tube brackets on said cover, one ci said tube brackets forming a terminal for a fuse tube, a lI'use tube carried by said brackets and slidabiy movable in said hinge member, a compression spring coiled about the tube and reacting between the hinge member and one or' said tube brackets, said hinge member constituting a secyond terminal for said tube, a lever pivoted to said hinge member, and a fuse link held electrically to the terminal forming tube bracket and adapted for anchorage to said lever to restrain said spring in compression.

16. In combination, a slidable fuse tube having spaced terminals and adapted to receive a fuse link for interconnecting said terminals, and a pivoted lever operated through a relatively short radius by the movement of said tube and adapted to be restrained by said link through a relatively long radius normally to restrain sliding movement of said tube and to produce a positive gap and extend the same rapidly "upon blowing of. the fuse.

17. In combination, a pair of contacts, a fuse for connecting said contacts, hinge means for said fuse, the fuse being slidable relative to said hinge means, means for locking said fuse to at least one of said contacts, and means operable upon blowing of the fuse for sliding the tube endwise relative to said hinge means for reducing the distance between said hinge means and said locking means to release said locking means; y

18. In combination, a housinggsa cover :for said housing, a fuse on said cover, hinge means for said cover, means slidably mounting said fuse on said hinge means, locking means for said cover, and means operable upon blowing of the fuse for reducing the distance between said hinge means and said locking means to release the locking means for said cover.

19. In combination, a housing, a pair of contact clips disposed in transversely spaced relation in said housing and having contacting and locking portions, a hinge member hinged to said housing, a cover for said housing, a pair of tube brackets on said cover, one having a portion movable into position between said clips when said cover is closed, a fuse tube carried by said brackets and slidably movable in said hinge member, a compression spring coiled about the tube and reacting between the hinge member and one or" said tube brackets, the other tube bracket having lateral studs electrically a part thereof and engageable with the contacting and locking portions oi the clip when the cover is closed, a lever pivoted to the hinge. member and operated by the movement of the tube in said hinge member, and a fuse link held electrically to the tube bracket with the lateral studs for engaging said clips and adapted to be anchored to said lever to restrain said spring.

20. in combination, a housing, a pair of contact clips disposed in transversely spaced relation in said housing and having contacting and locking portions, a hinge member hinged to said housing, a cover ior said housing, a pair of tube brackets on said cover, one having a portion movable into position between said clips when said cover is closed, a iuse tube carried by said brackets and slidably movable in said hinge member, a compression spring coiled about the tube and reacting between the hinge member and one of said tube brackets, the other tube bracket having lateral studs electrically a part thereof and engageable with the contacting and `locking portions of the clip when the cover is closed, a lever pivoted to the hinge member and operated by the movement of the tube in said hinge member, a fuse link held electrically to the tube bracket with the lateral stuls for engaging said clips, and a pivoted wedge member for anchoring said link to said lever.

21. In combination a contact comprising a contact base and a contact clip secured to said base and having a generally goose-neck portion presenting a contact portion .along its free end, a pivotally mounted conducting member adapted to swing against said free end to hex the clip, and a fuse for holding said pivotally mounted member in said clip fi Xing position.

22. In combination a fuse device mounted for swinging motion, said device having a terminal; element a contact comprising a contact base mounted adjacent said terminal element, a clip secured to said base and having a generally goose-neck portion presenting a contact portion along its free end, and a contact spring secured to said base and having a generally goose-neck portion nested within the generally goose-neck portion of said clip and bearing against the clip to press the contact portion of the clip to rm engagement with said terminal element, said device comprising fusible means for holding said element in position vto be engaged by said contact portion of the clip.

23. In combination, a housing, a hinge member hinged to said housing, a fuse having a tube slidably movable in said hinge member, and a cover for the housing attached to said tube.

24. In combination, a housing, a hinge member hinged to said housing, a fuse having a tube slidably movable in said hinge member, a cover for the housing attached to said tube, and a spring for moving said tube slidably in said hinge member.

25. In combination, a housing, a hinge member hinged to said housing, a fuse having a tube slidably movable in said hinge member, a cover for the housing attached to said tube, a spring for moving said tube slidably in said hinge member, a fuse link within said tube, and a pivoted lever for anchoring said link and operated by movement of the tube in said hinge member.

26. In a cutout, a housing having opposite side walls, hinge brackets, one on each of said side walls and each having two substantially parallel grooves for engaging a pair of hinge pins, a cover for said housing, a fuse tube on said cover, and a hinge member slidably receiving said tube and having at each of its opposite sides a pair of hinge pins engaging in said grooves.

27. In a cutout comprising a housing, a fuse having a tube and a cover for the housing attached to said fuse tube, the combination of a pair of hinge brackets each adapted for engagement with a pair of hinge pin's and each having a pair of tracks, one of which includes means to stop the tube and cover in an open position, andy the other having means to take the recoil upon blowing of the fuse and two pairs oi' hinge pins for the cover, each pair cooperating with one of the hinge brackets.

28. In a cutout comprising a housing, a fuse having a tube and a cover for the housing attached to said tube, the combination oi' a pair oi' hinge brackets each adapted for engagement with a pair of hinge pins and each having a pair of tracks arranged to permit lifting the cover and tube from the bracket in an open position and including means for holding the cover and tube against removal in closed position and in movement toward open and closed positions and two pairs of hinge pins for the cover, each pair cooperating with one of the hinge brackets.

29. In a cutout comprising a housing and a cover for the housing, a pair of hinge brackets each provided with two stop means, one to engage against drop-out when the cover is open and the other to engage against recoil when the cover is closed and two pairs of hinge pins for the cover, each pair cooperating with one of the hinge brackets. i.

30. In a cutout having a fuse and a cover, a pair oi' hinge brackets arranged to permit lifting the fuse and cover from the bracket in an open position of the cover, and having stop means for taking the recoil and preventing lifting of the tube and cover from the bracket in closed and intermediate positions, the cover having a pair of hinge pins and a pair of stop pins cooperating with said brackets.

31. In a cutout having a fuse, a hinge bracket having a pair of adjacent curved grooves, a member having a pair of hinge pins engaging in said grooves, a track between said grooves and including an upturned stop to prevent said mem-v ber from dropping out in an open position and permitting lifting of said member from said bracket in opcn position, a track along the other groove extending upwardly and hooked inwardly to take the recoil upon blowing of the fuse, and a second track along said first groove for forcing one of said hinge pins under the inwardly hooked portion of said last track to prevent lifting the member out of the bracket in closed and intermediate positions.

32. In a device of the class described, a housing having a pair of contacts, a cover for said housing, a fuse on said cover for connecting said contacts in closed position of said cover, means slidably mounting said fuse in said housing, means for locking said cover closed and said fuse to one of said contacts and against sliding movement, and spring means to release said locking means and simultaneously elongate the arc upon blowing of the fuse.

33. In a device of the class described, a housing having a pair of contacts, a cover for said housing, a fuse on said cover for connecting said contacts in closed position of said cover, means slidably mounting said fuse in said housing. means for locking said cover closed and said fuse to one of said contacts and against sliding movement, spring means to release said locking means and simultaneously elongate the arc upon blowing of the fuse, said fuse including a fuse link for restraining said spring means, and a lever for giving the fuse link mechanical advantage over said spring means and operable upon blowing of the fuse tomultiply the speed of elongation of the arc.

34. In a fuse, an insulatingouter sleeve having spaced terminals, la. fuse link connected between said terminals and disposed within said sleeve, a coiled compression spring externally surrounding the sleeve for producing a positive gap and elongating the gap when the fuse blows, said spring being normally restrained by said fuse link, and lever means for giving the fuse link a mechanical advantage over said spring means and operable upon blowing of the fuse to multiply the speed of elongation of the arc.

35. In a fuse, an outer insulating member having a bore of relatively large diameter, a pair of terminals comprising a stationary terminal and a movableterminal and a fusible element connecting said terminals, an inner insulating member having a bore of relatively small diameter closely surrounding said terminals and fusible element, said inner insulating member terminating immediately below the movable terminal and beingvclosed at one end by said stationary terminal and secured to said stationary terminal, and being fully open at the other end to permit free expulsion of the movable fuse terminal and means for moving the movable terminal when the fusible element fuses to lengthen the arc first within the bore of the inner insulating member and later within the bore of the outer insulating member.

36. In a fuse, an outer insulating member having a bore of relatively large diameter, apair of fuse terminals comprising a stationary terminal and a movable terminal and a fusible element connecting said terminals, an inner insulating member having a bore of relatively small diameter closely surrounding said terminals and fusible element, said .inner insulating member being closed at one end by said stationary terminal and secured to said stationary terminal. said .inner insulating member terminating below the within the bore of the outer insulating member.

37. In a fuse, an outer insulating member having a bore of relatively large diameter, a pair of frise terminals comprising a stationary terminal and a. movable terminal and a fusible element connecting said terminals, an inner insulating member having a bore of relatively small diameter closely surrounding said terminals and fusible element, said inner insulating member terminating approximately midway of the length vantage over said spring means and operable upon blowing of the fuse to multiply the speed of elongation of the arc.

38. In a fuse, an outer insulating sleeve, an inner insulating sleeve having a bore of relatively small diameter, a pair of terminals and a fusible element closely surrounded by the bore of the inner sleeve, means on one oi said terminals for anchoring the same upon the adjacent end of the outer sleeve, one end of the inner sleeve being closed by and attached to said latter terminal the other end terminating substantially midway of the length of the bore of the outer sleeve and being open for the tree expulsion ofthe other fuse terminal, means extending from the other terminal outside of said outer insulating sleeve, and spring means externally of the outer sleeve operatively connected to said means extending from said other terminal for moving the same when the fusible element fuses to lengthen the arc first within the bore of the inner sleeve and later within the bore of the outer sleeve.

39. In combination, a fuse tube member, a tube terminal closing one end, a sleeve-like tube terminal member slldable on the other end of the tube, a coiled compression spring embracing the tube and tending to move the sleeve-like terminal member along the tube member, a fuse link in said tube connected at its upper end to the said tube terminal, and a second class lever` pivoted at one end to one of the members and anchored at its free end to the fuse link and being engaged intermediate its ends by the other of said members to put the link under tension.

40. In a dropout boxed fuse, the combination venting said fuse tube from sliding downwardly, l

lid and fuse tube carried thereby at the lower end of said box whereby they can be detached from said box as a unit for replacing a blown fuse link.

41. In a dropout yboxed fuse, the combination of a box having back, side and top' walls, the box being open at the front and bottom, a lid for closing the open front, upper and lower line terminals on said back wall, an expulsion fuse tube carried by said lid, tube terminals for said fuse tube adapted to engage said line terminals one closing the upper end of said fuse .tube and the other slidably mounting said\fuse tube, said fuse tube being biased for sliding movement downwardly through said other tube terminal and adapted to receive a fuse link therein ,for 'interconnecting said tube terminals, allever pivoted on said other tube terminal and restrained by said fuse link as iong as it remains intact for holding said oney tube terminal in contact engagement with said upper'line terminal and prethe force biasing said fuse tube downwardly acting through said lever to tension said fuse link, and separable hinge means for mounting said lid and fuse tube carried thereby at the lower end or' said box whereby they can be detached from said box as a unit for replacing a blown fuse link.

42. In a dropout boxed fuse, the combination of a box having an open front, a lid for closing f said open front, an expulsion fuse carried on the inside of the lid, said fuse comprising a tube having an upper terminal for normally closing the upper end of the tube, said terminal being iixed to the tube an' having a lower terminal member loosely emb acing and slidable on the lower end oi the tube', a coil spring encircling the tube and tending to produce movement of the tube relative to the lower terminal, a fuse link for restraining movement of said fuse tube relative to said lower terminal, and a pair of contact springs mounted in the box, one of said springs l engaging the upper terminal to hold the lid on of a box having back, side and top walls, the box =tube being. biased for sliding movement downwardly through said other tube terminal and Y adapted to receive a fuse link therein for interconnecting said tube terminals,` a. lever pivoted von said other tubeterminal and .restrained by said inse link as long as it remains intact foi" holdingl said one tube terminal in contact en-` gagement with said upp'er line terminal and preventing said fuse tube from sliding downwardly, and separable hinge 'means for mounting said the box so long as said fuse link is intact and another of said contact springs engaging the lower terminall member.

43. In combination in-a boxed dropout fuse, a box having an opening in its front, a-lid for cov ering said opening, a separable hinge between the lid and the box comprising a box hinge member and a lid hinge member, a fuse carried on the lid, said fuse having a fuse tube with an upper terminal nxed on the upper'end of the tube and va lower-terminal slidable on the lower end of the tube, a compression spring surrounding the tube for sliding the tube relative to the lower terminal, a fuse link for the tube for connecting said tube terminals, said Vlink when intact holding said spring compressed to keep the tube terminals from approaching each other by expansion of said spring, a spring mounted xedly in the box and adapted to engage and hold the upper fuse terminal when the fuse tube is in extended position relative to the lower terminal and to re. lease the upper fuse terminalwhen the tube ls in retracted position relative to the fusejterminal, and a spring mounted lxedly in the box and adapted to engage the lower tube terminal, said springs mounted in the box having a xed spacing relative to the box hinge memberfand the lower tube terminal having a ilxed spacing relative to the lid hinge member. f

44. In a fuse device, amounting comprising support having an upper contact and a lower contact, said upper contactxhaving a portion serving as a spring detent, a hinge member on said support, a fuse tube having a closed upper terminal iixed thereupon and provided with a shoulder cooperating with the spring detent portion oi.' the upper contact, a lower tube terminal slidably mounted on the lower end of the tube, a collar on the tube adjacent the lower terminal, a coiled spring surrounding the tube and disposed between the lower terminal and said collar, a fuse link for restraining movement of said tube relative to said lower terminal, and a hinge member iixed relative to said lower tube terminal.

45. The combination of claim 44 wherein said hinge members are separable and have cooperating shoulders to stop the fuse tube when it has travelled through substantially ninety degrees, said hinge members being disengageable only upon raising the fuse tube angularly to disengage said shoulders and lifting the fuse hinge member from the hinge member on the support.

46. The combination of claim 44 wherein the lower terminal member has snubbing means for clamping the lower end of the. fuse link, said snubbing means being energized by the action of said coiled spring.

47. In a fuse of the class described, a fuse tube, a iuse link in the tube provided with a terminal lead, a sleeve movable with respect to the tube, a spring for producing relative movement of the sleeve and tube when the link is melted, an arm ivoted to the sleeve and cooperating with the rminal lead for retracting it at an' accelerated rate when the link melts, and means on said tube engaging said arm to cause it to swing away from the adjacent end of the tube when the link is melted.

48. In a circuit interrupter, in combination, a first and a second stationary terminal, afuse tube having fuse terminals and a fuse link therevin electrically interconnecting them, one of said fuse terminals being in contact engagement with said iirst stationary terminal, the other of said fuse terminals comprising a metallic sleeve through which said fuse tube is relatively movable and being electrically connected to said second stationary terminal, and a spring biasing said fuse tube for relative movement through said sleeve,said fuse linkbeing tensioned by said spring and 'releasing the same on blowing to produce said relative movement for disengaging said one fuse .terminal from said rst stationary terminal.

49. A circuit interrupting switch structure comprising a housing having an open bottom and having contacts, guiding means mounted within the housing,` an arcing tube slidably supported within said guiding means, a spring encircling said tube and urging said tube towards said open bottom, said tube having spaced contacts normally electrically connected to said'i'lrst kmentioned contacts, a iiexible conductor in said tube electrically joining said spaced contacts, a lever for releasably latchingsaid tube in operative position, said lever being urged to releasing position by means of said spring and pulling said conductor from said tube when released, and current controlled means for releasing said lever under overload conditions.

50. In a 'circuit interrupter, in combination, a first and a second stationary terminal, a fuse tube having fuse terminals and a fuse link therein electrically interconnecting them, one of said fuse terminals being in contact engagement with said first stationary terminal, the other of said fuse terminals comprising a metallic sleeve through which said fusetube is relatively movable Aand belng electrically connected to said second stationary terminal, means providing a hinged support for said sleeve adjacent said second stationary terminal, and means for producing relative movement between said fuse tube and said sleeve in response to blowing of said fuse link to disengage said one fuse terminal from said iirst stationary terminal and permit said fuse tube to swing with said sleeve about said hinged support.

5l. In a circuit interrupter, in combination, a ilrst and a second stationary terminal. a fuse tube having fuse terminals and a fuse link therein link thereto at a point remote from its axis oi' rotation until said fuse link blows and being arranged and adapted to give said fuse link a mechanical advantage over said spring and operable upon blowing of said fuse link to multiply the speed of elongation of the arc.

52. In a circuit breaker, spaced contact terminals, means for mounting a fuse housing connected between said terminals including a hinged support for the fuse housing arranged to provide for longitudinal sliding of the fuse housing relative to the hinged support, latching means for normally holding the fuse housing against such longitudinal sliding, said latching means being arranged'xto be released by operation of a fuse in the fuse housing thereby to permit longitudinal sliding of the fuse housing, means arranged to be released by longitudinal movement of the fuse housing for holding the fuse housing between said terminals, and means for swinging said housing from between said terminals upon release of said last mentioned holding means.

53. In a circuit interrupter, a container, a closure member therefor pivotally mounted on the container, holding means normally preventing pivotal movement of said closure-member, a fuse tube mounted in said container for movement out of said container upon pivotal movement of said closure member, said fuse tube being movable without pivotal movement of said closure meniber to cause release of said holding means and permit pivotal movement of said closure member, and a fusible member in said fuse tube for controlling the said release movement of the fuse tube.

54. In a fuse device, a housing, a door for said housing pivotally mounted thereon, a fuse tube having a fusible link therein movably supported within said housing, said fuse tube being movable without pivotal movement of said door to cause said door to open, and means controlled by said fusible link for restraining said fuse tube against motion.

55. In a circuit opener, a container, a closure therefor connected by a pivotal connection onto the container, said closure being slidable relative to the container when the closure is in closed position, a fusible element in the container normally preventing said sliding movement but permitting said sliding movement when fused, and

latching means normally holding the closure in closed position, said latching means cooperating with said pivotal connection to hold lsaid closure being released following said predetermined sliding movement to enable said closure to rotate about said pivotal connection to the open position.

56. In a circuit interrupter, a housing, a door for said housing, a fuse assembly mounted on said door including a fusible element, pivot means supportingsaid door and fuse assembly, said door being slidable between predetermined limits with respect to said housing, a control member carried by said door movable between predetermined positions, said control member being restrained in one position by said fusible element for holding said door against sliding movement, biasing means for moving said control member to another position upon fusion of said fusible element to cause said predetermined sliding movement of said door, and latching means for normally holding said door in closed position, said latching means holding said door againstrota- -tion about said pivot means upon fusion of said fusible element during a portion of said sliding movement and beingadapted to release said door upon the completion of said sliding movement to cause the door to rotate about said pivot means "to the open position.

ably moved with respect to said housing upon rrupture of said fuse link for detaching said latching means.

58. In a fuse device, a housing, a dooi` for-said housing, pivot means supporting said door for swinging'movement with respect to said housing, said door beingslidable relative to said housing when the door is in closed position, a fuse tube carried by said door, a fusible link within said fuse /,tube, latch means normally operative to hold said door closed when the latter isl in a predetermined position, and biasing means for sliding said door from said predetermined position to detach said latch means, vsaid fusible link normally restraining said door against movement by said biasing means.

59. In a fuse device, a housing, a housing pivotally mounted thereon, holding means normally preventing pivotal movement of said door, a fuse tube within said housing carried by said door and adapted to be moved out of said housing upon pivotal movement of said door, said door and fuse tube being slidable relative to said housing without pivotal movement of said door to cause release of said holding means and permit pivotal movementof said door to the open position, and a fuse link in said fuse tube for controlling the said release movement of said door and fuse tube.

60. A fuse construction comprising a stationary support having stationary contacts, a fuse tube slidably supported from said stationary support and having an open end, a fuse link within said fuse vtube projecting. from said open end and normally electrically connecting said stationary contacts, and means controlled by said fuse link ,and located adjacent the open end of said fuse tube for normally holding said fuse tube against sliding motion and for extracting said fuse link when said fuse link is ruptured, said means having a portion for drawing said fuse link outwardly substantially in line with said fuse tube.

61. A fuse construction comprising a stationary support having stationary contacts, a fuse tube slidably supported from said stationary support` and having an open end, a fuse link within said fuse tube projecting from the open end of said fuse tube and normally electrically connecting said stationary contacts, and means biased towards releasing motion normally holding said fuse tube against sliding motion and controlled by said fuse link, said means having motion substantially directly away from the open end of said fuse tube and substantially in line with said fuse tube, said member engaging said fuse link for withdrawing said fuse link from said fuse tube upon rupture of said fuse link.

62. A fuse construction comprising a stationary support having stationary contacts, a fuse tube slidably supported from said stationary support and having an open end, a. fuse link within said fuse tube and projecting from. the open end thereof, fuse link extracting means having one portion thereof located adjacent the open end of said fuse tube and movable substantially directly outwardly from the open end of said fuse tube in approximate line with said fuse tube for a part of the motion of said fuse link extracting closing the open front, upper and lower line terdoor for-said minals on said back wall, an expulsion fuse tube carried by said lid, tube terminals i'or said fuse tube adapted to engage said line terminals one closing the upper end of said fuse tube and the other slidably mounting said fuse tube, said fuse tube being biased for sliding movement downwardly through said other tube terminal and adapted to receive a fuse link therein for interconnecting said tube terminals, a lever pivoted on said other tube terminal and restrained by said fuse link as long as it remains intact for holding said one tube terminal in contact engagement with said upper line terminal and preventing said fuse tube from sliding downwardly, and

separable hinge meansfor mounting said lid and fuse tube carried thereby at the lower end of said box whereby they can be detached from said box as a unit for replacing a blown fuse link, said hinge means comprising a pairof hinge members secured to said .side walls adjacent their lower outer ends and hinge pins detachably cooperating therewith.

64. In a dropout boxed fuse, the combination of a box having back, side and top Walls, the box being open at the front and bottom, a lid for closing the open front, upper and lower line terminals on said back wall, an expulsion fuse tube carried by said lid, tube terminals for said fuse tube adapted to engage said line terminals one closing the upper end of said fuse tube andi/the other slidably mounting said fuse tube, said fuse tube being biased for sliding movement downwardly through said other tube terminal and adapted to receive a fuse link therein for interconnecting said tube terminals, a lever pivoted on said other tube terminal and restrained by said fuse link as long as it remains intact for holding said one tube terminal in contact engagement with said upper line terminal and preventing said fuse tube from sliding downwardly, the force biasing said fuse tube downwardly acting through said lever to tension said fuse link, and separay ble hinge means for mounting said lid and fuse tube c arried thereby at the lower end of said box whereby they can be detached from said box as a unit for replacing a blown fuse link, said hinge means comprising a pair of hinge members secured to said side walls adjacent their lower outer ends and hinge pins detachably cooperating therewith.

65. In a fuse, a slidably mounted insulating sleeve` having spaced terminals, said sleeve being adapted. to receive therein a fuse link for interconnecting said terminals, and means for producing a positive gap and for extending the gap when the fuse link blows, said means comprising lever means disposed transversely of and opposing movement of the sleeve and a spring disposed externally and at one end of said outer sleeve.

66. In a fuse, a fuse tube having spaced terminals, there` being relative movement between said tube and`one of said terminals, said fuse tube being adapted to receive a fuse link therein for interconnecting said terminals, and means for translating the relative movement between said tube and terminal to produce a positive gap and extend said gap when the fuse link blows,

said means comprising a lever pivoted to said one said one end to said tube terminal with the other end of the fuse link extending out of the open other end of said fuse tube member for connection to said sleeve-like tube terminal member, and a second class lever pivoted at one end to one of said members and restrained at its free end by the fuse link and being engaged intermediate its ends by the other of said members to put the fuse link under tension.

68. A circuit interrupting switch structure comprising a housing having an open bottom and having contacts, an arcing tube slidably supported within said housing, spring means urging said tube towards said open bottom, said tube having spaced contacts normally electrically connected to the ilrst mentioned contacts, aexible conductor in said tube electrically joining said spaced contacts, a lever releasably latching said tube in operative position, said lever being urged to releasing position by said spring means and v'pulling said conductor from said tube when released, and current controlled means for releasing said lever under overload conditions.

69. A circuit interrupting switch structure comprising a housing having an open bottom and having contacts, an arcing tube slidably supported within said housing, spring means urging said tube towards said open bottom, said tube having spaced contacts normally electrically connected to the first mentioned contacts, a iiexible conductor in said tube' electrically joining said spaced contacts, a lever releasably latching said tube in operative position, said'lever being urged to releasing position by said spring 'means and pulling said conductor from said tub'e when released, and current controlled means for releasing said lever under overload conditions comprising a fusible element and a parallel strain element, said strain element relieving said fusible element of stress otherwise applied thereto by said spring means.

70. In a circuit interrupter, in combination, a ilrst and a second stationary` terminal, a fuse tube having fuse terminals and a fuse link therein electrically interconnecting them, one oi' said fuse terminals being in contact engagement with said rst stationary terminal, the other of said fuse terminals comprising a metallic sleeve through which said fuse tube is relatively movable and being electrically connected to said second stationary terminal, and a spring biasing said fuse tube for relative movement through said sleeve. said fuse link being tensioned by said spring and releasing the same on blowing to produce said relative movement for disengaging said one fuse terminal from said irst stationary terminal, said fuse link including a fusible section and a parallel strain section, said strain section relieving said fusible section of stress-otherwise applied thereto by said spring.

71. In a circuit interrupter, in combination, a pair of terminals in insulated spaced relation,

and a fuse device for interconnecting said terminals including a fuse tube adapted in its normal position to receive a replaceable fuse link, means slidably mounting said fuse tube, said fuse tube being biased from said normal position and the force biasing said fuse tube being restrained by said fuse link, and a lever restrained in its normal position by said fuse link and biased to an alternate `position for withdrawing a remaining portion of said fuse link after the same blows i'or extending .and extinguishing the arc incident to blowing of the fuse link.

'72. In a circuit interrupter, in combination, a fuse tube having terminals at its ends and adapted to receive a replaceable fuse link for interconnecting said terminals, one of said terminals closing one end of said fuse tube, the other end of said fuse tube lbeing open, a lever mounted on the other of said terminals and extending across said open end of said fuse tube and having an opening through which said fuse link ispassed, and means biasing said lever away from said operi end of said fuse tube, said lever being restrained by said fuse link as long as the same remains intact and adapted to withdraw a remaining portion of said fuse link when the same blows substantially in line with said fuse tube.

'13. In combination, a slidable fuse tube having spaced terminals and adapted to receive a fuse link for interconnecting said terminals, a lever pivoted to one of said terminals and operated through a relatively short radius by the movement of said fuse tube and adapted to be restrained by said link through a` relatively long radius normally to restrain sliding movement of said fuse tube, and an auxiliary lever pivoted on said lever and cooperating therewith to produce a positive gap and extend the same,r rapidlyv on blowing of said fuse link.

ALLAN RAMSEY. 

